For mining litecoin I am using R7 260x. But even after tweaking it gives a max of 170 kH/s.

My setting looks like this:

{ "pools" : [     {         "url" : "stratum+tcp://*************",         "user" : "************",         "pass" : "***********"     } ] , "intensity" : "13", "vectors" : "1", "worksize" : "256", "kernel" : "scrypt", "lookup-gap" : "2", "thread-concurrency" : "8192", "shaders" : "2048,", "gpu-engine" : "1050", "gpu-fan" : "0", "gpu-memclock" : "1200", "gpu-memdiff" : "0", "gpu-powertune" : "20", "gpu-vddc" : "0.000", "temp-cutoff" : "75", "temp-overheat" : "85", "temp-target" : "65", "api-port" : "4028", "expiry" : "120", "gpu-dyninterval" : "7", "gpu-platform" : "0", "gpu-threads" : "2", "hotplug" : "5", "log" : "5", "no-pool-disable" : true, "queue" : "1", "scan-time" : "60", "scrypt" : true, "temp-hysteresis" : "3", "shares" : "0", "kernel-path" : "/usr/local/bin" } 

And the graphic card default setting looks like this :

Is there a way to teak the settings a bit so that I can get 400-500 kH/s, or should I invest totally in a new graphic card?

Also is there a way I can pool another cryptocurrency which might be profitable with this Graphic card?